Silicone compositions

ABSTRACT

This invention relates to a method of improving the stability of a bleach and lipophile composition comprising an inorganic persalt bleaching agent and a lipophile selected from the group consisting of flavorants, perfumes, coolants, antimicrobial agents, and mixtures thereof, by inclusion of an aminoalkylsilicone, having an aminoalkylsiloxane content of from about 0.1% to 2% on a repeating unit basis.

This application is a 371 of PCT/US95/15765, filed Dec. 5, 1995.

TECHNICAL FIELD

The present invention relates to silicone-containing compositions and touse thereof in various household products such as personal careproducts, laundry and household cleaners, bleaching compositions and thelike. In particular, it relates to silicone-containing lipophiliccompositions based on flavorants, perfumes, coolants or antimicrobialagents as lipophile and which display improved residuality, impactand/or efficacy on surfaces treated therewith, for example teeth,dentures, skin, hair, laundry, dishware, working surfaces and the like.In addition, it relates to silicone-containing bleach compositions whichadditionally contain bleach-sensitive ingredients such as perfumes,flavorants and the like and which display improved stability.

BACKGROUND

Lipophilic compositions such as flavor, perfume, coolant anddisinfectant compositions are widely used either directly or in avariety of household products inclusive of cosmetics, oral and denturecompositions, bleach, dishwashing, hard surface cleaning and laundrydetergent products, etc. A common problem encountered with lipophiliccompositions is that of improving surface substantivity or residualityof the lipophilic component. It would be desirable in many if not mosthousehold applications to enhance the surface residuality of thelipophile in order, for example, to provide increased flavor or perfumeimpact or increased antimicrobial efficacy.

Modern dental hygiene and denture preparations, for example, typicallycontain antiplaque and/or antitartar agents, as well as antimicrobialagents and flavorants. Antimicrobial action could affect plaqueformation by either reducing the number of bacteria in themouth/dentures or by killing those bacteria trapped in the film toprevent further growth and metabolism. Flavorants may alleviate theproblem of bad breath via a deodorizing action. Some antimicrobialagents, e.g. menthol may, also serve as breath deodorizers. However, theefficacy of antimicrobial agents depends largely on theirintraoral/denture retention, particularly their retention on the surfaceof the teeth or dentures where plaque is formed.

A typical disadvantage of known dental preparations is that only arelatively short time during which the teeth are being cleaned or themouth is being rinsed is available for antimicrobial agents in thepreparations to take effect. The problem is compounded by the fact thatdentifrice preparations are used infrequently; most are used once or,perhaps, twice daily. Consequently, the long time period betweenbrushings for a majority of the population provides optimum plaqueforming conditions.

In many other personal and household applications, it would be desirableto provide enhanced surface substantivity. Laundry detergents, forexample, would benefit by increasing perfume substantivity on fabrics soas to provide increased perfume impact on clothing after laundering orduring use. Increased antimicrobial substantivity would also bebeneficial from the viewpoint of reducing malodors associated with sweator other soils. Enhanced perfume substantivity would also be valuable infine fragrance and perfumed cosmetics. Enhanced coolant substantivity,on the other hand, would be beneficial in cough/cold products.

There has been a need, therefore, for developing lipophilic compositionswhich have improved surface residuality, impact and/or antimicrobialefficacy.

The use of lipophilic compounds such as perfumes, flavorants and thelike in bleach-containing compositions can also raise a number ofproblems, especially loss of perfume or flavorant character or intensityas a result of interaction with the bleach. The efficacy of thebleaching agent can also be adversely effected. It would thus bedesirable to improve the stability and effectiveness of bleachcompositions containing bleach-sensitive ingredients.

It is known to include silicones in dentifrice compositions, allegedlyto coat the teeth and prevent cavities and staining. For instance,GB-A-689,679 discloses a mouthwash containing an organopolysiloxane forpreventing adhesion of, or for removing tars, stains, tartar and foodparticles from the teeth. The mouthwash may include antisepticcompounds, such as thymol, and flavoring and perfuming agents.

U.S. Pat. No. 2,806,814 discloses dental preparations including, incombination, a higher aliphatic acyl amide of an amino carboxylic acidcompound as an active and a silicone compound. The patent notes thatsilicone compounds have been proposed for prevention of adhesion or tofacilitate the removal of tars, stains, tartar and the like from teeth.The silicone compound is said to act as a synergist in improving theantibacterial and acid inhibiting activity of the active ingredient.Dimethyl polysiloxanes are said to be particularly effective. Flavoringoils and/or menthol may be included.

U.S. Pat. No. 3,624,120 discloses quaternary ammonium salts of cyclicsiloxane polymers for use as cationic surfactants, bactericides and asanticariogenic agents.

Accordingly, the present invention provides a flavor, perfume, coolant,antimicrobial or other lipophilic composition having improvedsurface-substantivity, impact and/or efficacy.

The invention further provides a bleach composition comprising aninorganic persalt bleaching agent, and a lipophilic compound such as aflavorant and/or perfume and which has improved stability.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided aflavor, perfume, coolant, antimicrobial or other lipophilic compositioncomprising an aminoalkylsilicone having an aminoalkylsiloxane content offrom about 0.1%-2% on a repeating unit basis.

The invention also relates to the use of an aminoalkylsilicone with alipophile selected from flavorants, perfumes, physiological coolants,antimicrobial agents and mixtures thereof to provide improved surfaceresiduality, wherein the aminoalkylsilicone is selected fromaminoalkylsilicones having an aminoalkylsiloxane content of from about0.1%-2% on a repeating unit basis.

According to a further aspect of the invention, there is provided ableach composition comprising an inorganic persalt bleaching agent, alipophile selected from flavorants, perfumes, physiological coolants,antimicrobial agents and mixtures thereof, and an aminoalkylsiliconehaving an aminoalkylsiloxane content of from about 0.1%-2% on arepeating unit basis.

The invention also relates to the use of an aminoalkylsilicone with aninorganic persalt bleaching agent and a lipophile selected fromflavorants, perfumes, physiological coolants, antimicrobial agents andmixtures thereof to provide improved lipophile stability, wherein theaminoalkylsilicone is selected from aminoalkylsilicones having anaminoalkylsiloxane content of from about 0.1%-2% on a repeating unitbasis.

All percentages and ratios herein are by weight of total composition,unless otherwise indicated.

The compositions of the invention thus comprise an aminoalkylsiliconeantiplaque agent and a lipophile selected from flavorants, perfumes,physiological coolants, antimicrobial agents and mixtures thereof. Othercompositions of the invention take the form of bleach and/or detergentcompositions which comprise the aminoalkylsilicone antiplaque agent andlipophile.

In general terms, the aminoalkylsilicone is selected from noncyclic,hydrophobic aminoalkysilicones having a formula comprising two basicunits:

1) (R¹)_(m) (R)_(n) SiO.sub.(4-m-n)/2 wherein m+n is 1, 2 or 3; n is 1,2 or 3; m is 0,1,2; and

2) (R¹)_(a) (R²)_(b) SiO.sub.(4-a-b)/2 wherein a+b is 1, 2, or 3, and aand b are integers,

wherein R¹ and R² are independently selected from H, alkyl and alkenylof about 1 to about 10 carbons optionally substituted with fluoro orcyano groups, hydroxy, alkoxy, and acetoxy, for example, wherein R¹ andR² are independently selected from methyl, ethyl, phenyl, vinyl,trifluoropropyl and cyanopropyl, and R is ##STR1## wherein R³ is adivalent alkylene of about 1-20, preferably about 3-5 carbon atomsoptionally substituted or interrupted by O atoms, R⁴, R⁵ and R⁶ whichmay be the same or different are selected from H, alkyl of about 1-20,preferably about 1-10, more preferably about 1-4 carbons optionallysubstituted or interrupted by N and/or O atoms, and X⁻ is a monovalentanion such as halide, hydroxide, and tosylate, said aminoalkylsiliconeincluding from about 0.1-2%, preferably from about 0.5-2% of unit (1) ona repeating unit basis.

In a preferred embodiment, the aminoalkylsilicones compriseamodimethicones. Amodimethicones are polydimethylsiloxane polymerscontaining aminoalkyl groups. The aminoalkyl groups may be presenteither pendant or at one or more ends of the polydimethylsiloxane chain.Preferred are aminoalkylsilicones in which aminoalkyl moiety R isselected from (CH₂)3NH₂, (CH₂)₃ NHCH₂ CH₂ NH₂, (CH₂)₃ N(CH₂ CH₂ OH)₂,(CH₂)₃ NH₃ ⁺ X⁻, and (CH₂)₃ N(CH₃)₂ (C₁₈ H₃₇)⁺ X⁻, and especially from(CH₂)₃ NH₂ and (CH₂)₃ NHCH₂ CH₂ NH₂. Also preferred are aminoalkylsilicones having an average molecular weight of about 5,000 and above,preferably from about 5000 to about 100,000, more preferably from about5000 to about 30,000.

Aminoalkylsilicone compounds suitable for use herein are well known.Methods of preparing aminoalkylsilicones are given in, for example, U.S.Pat. No. 2,930,809.

Examples of amodimethicones include OSI's Magnasoft fluid. Thesepolymers comprise aminoalkyl groups affixed to a predominantlypolydimethylsiloxane structure. The typical structure of Magnasoft'saminoalkyl group-containing units is

    --OSi(Me)C.sub.3 H.sub.6 NHCH.sub.2 CH.sub.2 NH.sub.2.

The aminoalkylsilicone is generally present in a level of from about0.01% to about 25%, preferably from about 0.1% to about 5%, morepreferably from about 0.5% to about 1.5% by weight.

The compositions of the invention preferably also include a lipophiliccompound. In general terms, lipophilic compounds suitable for use hereinare oil-like materials which are soluble or solubilisable in theaminoalkylsilicone, preferably at a level of at least about 1%, morepreferably at least about 5% by weight at 25° C. Preferred lipophiliccompounds are selected from flavorants, perfumes, physiological coolingagents and antimicrobial compounds. The aminoalkylsilicone acts toenhance the substantivity of the lipophilic compound to a surfacetreated therewith, thereby providing enhanced and/or sustained flavor,perfume or coolant impact and/or antimicrobial efficacy.

Lipophilic flavorants suitable for use herein comprise one or moreflavor components selected from wintergreen oil, oregano oil, bay leafoil, peppermint oil, spearmint oil, clove oil, sage oil, sassafras oil,lemon oil, orange oil, anise oil, benzaldehyde, bitter almond oil,camphor, cedar leaf oil, marjoram oil, citronella oil, lavendar oil,mustard oil, pine oil, pine needle oil, rosemary oil, thyme oil,cinnamon leaf oil, and mixtures thereof.

Lipophilic perfumes suitable for use herein comprise one or more knownperfume components inclusive of natural products such as essential oils,absolutes, resins, etc., and synthetic perfume components such ashydrocarbons, alcohols, aldehydes, ketones, ethers, acids, esters,acetals, ketals, nitriles etc., including saturated and unsaturatedcompounds, aliphatic, carboxylic and heterocyclic compounds. Examples ofperfume materials suitable for use herein include geranyl acetate,linalyl acetate, citronellyl acetate, dihydromyrcenyl acetate, terpinylacetate, tricyclodecenyl acetate, tricyclodecenyl propionate,2-phenylethyl acetate, benzyl acetate, benzyl salicylate, benzylbenzoate, styrallyl acetate, amyl salicylate, methyl dihydrojasmonate,phenoxyethyl isobutyrate, neryl acetate, trichloromethyl-phenylcarbinylacetate, p-tertiary butyl-cyclohexyl acetate, isononyl acetate, cedrylacetate, vetiveryl acetate, benzyl alcohol, 2-phenylethanol, linalool,tetrahydrolinalool, citronellol, dimethylbenzylcarbinol,dihydromyrcenol, tetrahydromyrcenol, terpineol, eugenol, geraniol,vetiverol, 3-isocamphyl-cyclohexanol, 2-methyl-3-(p-tertiarybutylphenyl)-propanol, 2-methyl-3-(p-isopropylphenyl)-propanol,3-(p-tertiary butylphenyl)-propanol, nerol, alpha-n-amylcinnamicaldehyde, alpha-hexyl-cinnamic aldehyde,4(4-hydroxy-4methylpentyl)-3-cyclohexenecarbaldehyde,4-(4methyl-3-pentenyl)-3-cyclohexenecarbaldehyde,4acetoxy-3-pentyl-tetrahydropyran, 2-n-heptyl-cyclopentanone,3-methyl-2-pentyl-cyclopentanone, n-decanal, n-dodecanal,hydroxycitronellal, phenylacetaldehyde dimethyl acetal,phenylacetaldehyde diethyl acetal, geranonitrile, citronellonitrile,cedryl methyl ether, isolongifolanone, aubepine nitrile, aubepine,heliotropine, coumarin, vanillin, diphenyl oxide, ionones, methylionones, isomethyl ionones, irones, cis-3-hexenol and esters thereof,indane musks, tetralin musks, isochroman musks, macrocyclic ketones,macrolactone musks, ethylene brassylate, aromatic nitromusks andmixtures thereof.

Lipophilic antimicrobial compounds suitable for use herein includethymol, menthol, triclosan, 4-hexylresorcinol, phenol, eucalyptol,benzoic acid, benzoyl peroxide, butyl paraben, methyl paraben, propylparaben, salicylamides, and mixtures thereof.

Physiological cooling agent suitable for use herein includecarboxamides, menthane esters and menthane ethers, and mixtures thereof.

Suitable menthane ethers for use herein are selected from those with theformula: ##STR2## where R₅ is an optionally hydroxy substitutedaliphatic radical containing up to 25 carbon atoms, preferably up to 5carbon atoms, and where X is hydrogen or hydroxy, such as thosecommercially available under the trade name Takasago, from TakasagoInternational Corporation. A particularly preferred cooling agent foruse in the compositions of the present invention is Takasago 10[3-1-menthoxy propan-1,2-diol (MPD)]. MPD is a monoglycerin derivativeof 1-menthol and has excellent cooling activity.

The carboxamides found most useful are those described in U.S. Pat. No.4,136,163, Jan. 23, 1979 to Wason et al., and U.S. Pat. No. 4,230,688,Oct. 28, 1980 to Rawsell et al.

The level of lipophilic compound in the compositions of the invention isgenerally in the range from about 0.01% to about 10%, preferably fromabout 0.05% to about 5%, more preferably from about 0.1% to about 3% byweight.

The compositions of the invention optionally include one or moresurfactants, these being especially preferred in lipophilic compositionsof the invention for the purpose of solubilization of the lipophile andfor providing improved efficacy. Suitable surfactants include non-soapanionic, nonionic, cationic, zwitterionic and amphoteric organicsynthetic detergents. Many of these suitable agents are disclosed byGieske et al. in U.S. Pat. No. 4,051,234, Sep. 27, 1977.

Examples of surfactants suitable for use herein include C₆ -C₁₈ alkylsulfates and alkyl ether sulfates ethoxylated with from about 0.5 toabout 20 moles of ethylene oxide per mole; anionic sulfonates inclusiveof C₅ -C₂₀ linear alkylbenzene sulfonates, alkyl ester sulfonates, C₆-C₂₂ primary or secondary alkane sulfonates, C₆ -C₂₄ olefin sulfonates,sulfonated polycarboxylic acids, alkyl glycerol sulfonates, fatty acylglycerol sulfonates, and mixtures thereof; anionic carboxylatesinclusive of primary and secondary C₆ to C₁₈ alkyl carboxylate, ethoxycarboxylate and polyethoxy polycarboxylate surfactants having an averagedegree of ethoxylation of from about 0 to about 10; C₅ -C₁₇ sarcosinatessuch as sodium cocoylsarcosinate, sodium lauroyl sarcosinate(Hamposyl-95 ex W. R. Grace); condensation products of ethylene orpropylene oxide with fatty acids, fatty alcohols, fatty amides,polyhydric alcohols (e.g. sorbitan monostearate, sorbitan oleate), alkylphenols (e.g. Tergitol) and polypropyleneoxide or polyoxybutylene (e.g.Pluronics); alkylpolysaccharides as disclosed in U.S. Pat. No.4,565,647; amine oxides such as dimethyl cocamine oxide, dimethyl laurylamine oxide and cocoalkyldimethyl amine oxide (Aromox); polysorbatessuch as Tween 40 and Tween 80 (Hercules); sorbitan stearates, sorbitanmonooleate, etc; cationic surfactants such as cetyl pyridinium chloride,cetyl trimethyl ammonium bromide, di-isobutyl phenoxy ethoxyethyl-dimethyl benzyl ammonium chloride and coconut alkyl trimethylammonium nitrate.

Highly preferred herein from the view point of lipophile solubilizationare the nonionic surfactants. One class of nonionic surfactant suitablefor use herein are those having the general formula: ##STR3## in whichR₁ is an alk(en)yl or alk(en)yl phenyl group having 8 to 22, preferably10 to 20 carbon atoms ion the alk(en)yl moiety and m and n representweight-averages in the range 0-80 and 2-80 respectively. Shorter chainlength alkyl groups are generally to be avoided for efficacy reasons andbecause unreacted fatty alcohol in such surfactants is a source ofmalodour and occasionally of skin irritation. It will be understood thatsurfactants of this type are usually mixtures of varying degrees ofethoxylation/propoxylation, accordingly m and n represent the respectiveweight-averages of the number of propoxylate and ethoxylate groups.Nonionic surfactants of the above general type include mixed alkoxylatesin which m and n are both in the range from about 2 to about 80, with mpreferably being in the range from about 2 to about 20, more preferablyfrom about 3 to about 10 and with n preferably being in the range fromabout 2 to about 60, more preferably from about 5 to about 50. One suchmaterial is PPG-5-ceteth-20 (available from Croda Inc as Procetyl AWS),where m and n have the values 5 and 20 respectively. Other suitablenonionic surfactants include polyethoxylated surfactants, e.g.ethoxylated alkylphenol ethers, particularly octyl- and nonylphenolethers containing 8-16 EO; ethoxylated aliphatic C₈ -C₂₀ alcohols, whichmay be linear or branched and contain 8-16, preferably 9-15 EO; andethoxylated hydrogenated castor oils.

In general, the ratio of surfactant to the perfume, coolant or otheroily material will be in the range of from about 50:1 to about 1:10,preferably from about 20:1 to about 1:2, more preferably from about 10:1to about 1:1.

Bleaching compositions of the invention additionally include one or morebleaching agents optionally together with organic peroxyacid precursors,effervescence generators, chelating agents, etc.

The bleaching agent takes the form of an inorganic persalt and can beselected from any of the well-known bleaching agents known for use inhousehold bleaches, detergents, denture cleansers and the like such asthe alkali metal and ammonium persulfates, perborates inclusive ofmono-and tetrahydrates, percarbonates (optionally coated as described inGB-A-1,466,799) and perphosphates and the alkali metal and alkalineearth metal peroxides. Examples of suitable bleaching agents includepotassium, ammonium, sodium and lithium persulfates and perborate mono-and tetrahydrates, sodium pyrophosphate peroxyhydrate and magnesium,calcium, strontium and zinc peroxides. Of these, however, the alkalimetal persulfates, perborates, percarbonates and mixtures thereof areprefered for use herein, highly preferred being the alkali metalperborates and percarbonates.

The amount of bleaching agent in the bleaching compositions of theinvention is generally from about 5 to about 70% preferably from about10% to about 50%.

The bleaching compositions can also incorporate an effervescencegenerator which in preferred embodiments takes the form of a solid basematerial which in the presence of water releases carbon dioxide oroxygen with effervescence. The effervescence generator can be selectedfrom generators which are effective under acid, neutral or alkaline pHconditions, but preferably it consists of a combination of a generatorwhich is effective or most effective under acid or neutral pH conditionsand a generator which is effective or most effective under alkaline pHconditions. Effervescence generators which are effective under acid orneutral pH conditions include a combination of at least one alkali metalcarbonate or bicarbonate, such as sodium bicarbonate, sodium carbonate,sodium sesquicarbonate, potassium carbonate, potassium bicarbonate, ormixtures thereof, in admixture with at least one non-toxic,physiologically-acceptable organic acid, such as tartaric, fumaric,citric, malic, maleic, gluconic, succinic, salicylic, adipic orsulphamic acid, sodium fumarate, sodium or potassium acid phosphates,betaine hydrochloride or mixtures thereof. Of these, malic acid ispreferred. Effervescence generators which are effective under alkalinepH conditions include persalts such as alkali and alkaline earth metalperoxoborates as well as perborates, persulphates, percarbonates,perphosphates and mixtures thereof as previously described, for example,a mixture of an alkali metal perborate (anhydrous, mono- ortetrahydrate) with a monopersulphate such as Caroat ^(R) marketed by E Idu Point de Nemours Co. and which is a 2:1:1 mixture of monopersulphate,potassium sulphate and potassium bisulphate and which has an activeoxygen content of about 4.5%.

In preferred bleaching compositions suitable for use as denturecleansers, the solid base material incorporates a (bi)carbonate/acideffervescent couple optionally in combination with aperborate/persulphate oxygen effervescence generator. The combination ofgenerators is valuable for achieving optimum dissolution characteristicsand pH conditions for achieving optimum cleaning and antimicrobialactivity. The (bi)carbonate components generally comprise from about 5%to about 65%, preferably from about 25% to 55% of the total composition;the acid components generally comprise from about 5% to about 50%,preferably from about 10% to about 30% of the total composition.

The bleaching compositions of the invention can be supplemented by otherknown components of such formulations. An especially preferredadditional component is an organic peroxyacid precursor, which ingeneral terms can be defined as a compound having a titre of at least1.5 ml of 0.1N sodium thiosulfate in the following peracid formationtest.

A test solution is prepared by dissolving the following materials in1000 mls distilled water:

    ______________________________________                                        sodium pyrophosphate    2.5 g                                                 (Na.sub.4 P.sub.2 O.sub.7.10H.sub.2 O)                                        sodium perborate        0.615 g                                               (NaBO.sub.2.H.sub.2 O.sub.2.3H.sub.2 O) having                                10.4% available oxygen                                                        sodium dodecylbenzene   0.5 g                                                 sulphonate                                                                    ______________________________________                                    

To this solution at 60° C. an amount of activator is added such that foreach atom of available oxygen present one molecular equivalent ofactivator is introduced.

The mixture obtained by addition of the activator is vigorously stirredand maintained at 60° C. After 5 minutes from addition, a 100 ml portionof the solution is withdrawn and immediately pipetted onto a mixture of250 g cracked ice and 15 ml glacial acetic acid. Potassium iodide (0.4g) is then added and the liberated iodine is immediately titrated with0.1 N sodium thiosulphate with starch as indicator until the firstdisappearance of the blue colour. The amount of sodium thiosulphatesolution used in ml is the titre of the bleach activator.

The organic peracid precursors are typically compounds containing one ormore acyl groups, which are susceptible to perhydrolysis. The preferredactivators are those of the N-acyl or O-acyl compound type containing aacyl radical R--CO wherein R is a hydrocarbon or substituted hydrocarbongroup having preferably from about 1 to about 20 carbon atoms. Examplesof suitable peracid precursors include:

1) Acyl organoamides of the formula RCONR₁ R₂, where RCO is carboxylicacyl radical, R₁ is an acyl radical and R₂ is an organic radical, asdisclosed in U.S. Pat. No. 3,117,148. Examples of compounds fallingunder this group include:

a) N,N-diacetylaniline and N-acetylphthalimide;

b) N-acylhydantoins, such as N,N'-diacetyl-5,5-dimethylhydantoin;

c) Polyacylated alkylene diamines, such asN,N,N'N'-tetraacetylethylenediamine (TAED) and the correspondinghexamethylenediamine (TAHD) derivatives, as disclosed in GB-A-907,356,GB-A-907,357 and GB-A-907,358;

d) Acylated glycolurils, such as tetraacetylglycoluril, as disclosed inGB-A-1,246,338, GB-A-1,246,339 and GB-A-1,247,429.

2) Acylated sulphonamides, such as N-methyl-N-benzoyl-menthanesulphonamide and N-phenyl-N-acetyl menthane sulphonamide, as disclosedin GB-A-3,183,266.

3) Carboxylic esters as disclosed in GB-A-836,988, GB-A-963,135 andGB-A-1,147,871. Examples of compounds of this type include phenylacetate, sodium acetoxy benzene sulphonate, trichloroethylacetate,sorbitol hexaacetate, fructose pentaacetate, p-nitrobenzaldehydediacetate, isopropeneyl acetate, acetyl aceto hydroxamic acid, andacetyl salicylic acid. Other examples are esters of a phenol orsubstituted phenol with an alpha-chlorinated lower aliphatic carboxylicacid, such as chloroacetylphenol and chloroacetylsalicylic acid, asdisclosed in U.S. Pat. No. 3,130,165.

4) Carboxylic esters having the gernal formal Ac L wherein Ac is theacyl moiety of an organic carboxylic acid comprising an optionallysubstituted, linear or branched C₆ -C₂₀ alkyl or alkenyl moiety or a C₆-C₂₀ alkyl-substituted aryl moiety and L is a leaving group, theconjugate acid of which has a pKa in the range from 4 to 13, for exampleoxybenzenesulfonate or oxybenzoate. Preferred compounds of this type arethose wherein:

a) Ac is R₃ --CO and R₃ is a linear or branched alkyl group containingfrom 6 to 20, preferably 6 to 12, more preferably 7 to 9 carbon atomsand wherein the longest linear alkyl chain extending from and includingthe carbonyl carbon contains from 5 to 18, preferably 5 to 10 carbonatoms, R₃ optionally being substituted (preferably alpha to the carbonylmoiety) by Cl, Br, OCH3 or OC₂ H₅. Examples of this class of materialinclude sodium 3,5,5-trimethylhexanoyloxybenzene sulfonate, sodium3,5,5-trimethylhexanoyloxybenzoate, sodium 2-ethylhexanoyloxybenzenesulfonate, sodium nonanoyl oxybenzene sulfonate and sodiumoctanoyl oxybenezenesulfonate, the acyloxy group in each instancepreferably being p-substituted;

b) Ac has the formula R₃ (AO)_(m) XA wherein R₃ is a linear or branchedalkyl or alkylaryl group containing from 6 to 20, preferably from 6 to15 carbon atoms in the alkyl moiety, R₅ being optionally substituted byCl, Br, OCH₃, or OC₂ H₅, AO is oxyethylene or oxypropylene, m is from 0to 100, X is O, NR₄ or CO--NR₄, and A is CO, CO--CO, R₆ --CO, CO--R₆--CO, or CO--NR₄ --R₆ --CO wherein R₄ is C₁ -C₄ alkyl and R₆ isalkylene, alkenylene, arylene or alkarylene containing from 1 to 8carbon atoms in the alkylene or alkenylene moiety. Bleach activatorcompounds of this type include carbonic acid derivatives of the formulaR₃ (AO)_(m) OCOL, succinic acid derivatives of the formula R₃OCO(CH₂)2COL, glycollic acid derivatives of the formula R₃₀ CH₂ COL,hydroxypropionic acid derivatives of the formula R₃ OCH₂ CH₂ COL, oxalicacid derivatives of the formula R₃ OCOCOL, maleic and fumaric acidderivatives of the formula R₃ OCOCH═CHCOL, acyl aminocaproic acidderivatives of the formula R₃ CONR₁ (CH₂)₆ COL, acyl glycine derivativesof the formula R₃ CONR₁ CH₂ COL, and amino-6-oxocaproic acid derivativesof the formula R₃ N(R₁)CO(CH₂)₄ COL. In the above, m is preferably from0 to 10, and R₃ is preferably C₆ -C₁₂, more preferably C₆ -C₁₀ alkylwhen m is zero and C₉ -C₁₅ when m is non-zero. The leaving group L is asdefined above.

5) Acyl-cyanurates, such as triacetyl- or tribenzoylcyanurates, asdisclosed in U.S. Pat. No. 3,332,882.

6) Optionally substituted anhydrides of benzoic or phthalic acid, forexample, benzoic anhydride, m-chlorobenzoic anhydride and phthalicanhydride.

7) N-acylated precursor compounds of the lactam class as disclosedgenerally in GB-A-855735, especially caprolactams and valerolactams suchas benzoyl valerolactam, benzoyl caprolactam and their substitutedbenzoyl analogs such as the chloro, amino, alkyl, aryl and alkoxyderivatives.

Of all the above, preferred are organic peracid precursors of types1(c), 4(a) and 7.

Where present, the level of peroxyacid bleach precursor by weight of thetotal composition is preferably from about 0.1% to about 10%, morepreferably from about 0.5% to about 5% and is generally added in theform of a bleach precursor agglomerate.

The bleach precursor agglomerates preferred for use herein generallycomprise a binder or agglomerating agent in a level of from about 5% toabout 40%, more especially from about 10% to about 30% by weightthereof. Suitable agglomerating agents include polyvinylpyrrolidone,poly (oxyethylene) of molecular weight 20,000 to 500,000,polyethyleneglycols of molecular weight of from about 1000 to about50,000, Carbowax having a molecular weight of from 4000 to 20,000,nonionic surfactants, fatty acids, sodium carboxymethyl cellulose,gelatin, fatty alcohols, phosphates and polyphosphates, clays,aluminosilicates and polymeric polycarboxylates. Of the above,polyethyleneglycols are highly preferred, especially those havingmolecular weight of from about 1,000 to about 30,000, preferably 2000 toabout 10,000.

Preferred from the viewpoint of optimum dissolution and pHcharacteristics are bleach precursor agglomerates which comprise fromabout 10% to about 75%, preferably from about 20% to about 60% by weightthereof of peroxyacid bleach precursor, from about 5% to about 60%preferably from about 5% to about 50%, more preferably from about 10% toabout 40% of a (bi) carbonate/acid effervescent couple, from about 0% toabout 20% of a peroxoboroate, and from about 5% to about 40%, preferablyfrom about 10% to about 30% of an agglomerating agent. The final bleachprecursor granules desirably have an average particle size of from about500 to about 1500, preferably from about 500 to about 1,000 um, thisbeing valuable from the viewpoint of optimum dissolution performance andaesthetics. The level of bleach precursor agglomerates, moreover, ispreferably from about 1% to about 20%, more preferably from about 5% toabout 15% by weight of composition.

The bleaching compositions of the invention can be in paste, tablet,granular or powder form. Compositions in tablet form can be single ormultiple layered tablets.

Bleaching compositions of the invention can be supplemented by otherusual components of such formulations, especially surfactants asgenerally described above, chelating agents, enzymes, dyestuffs,sweeteners, tablet binders and fillers, foam depressants such asdimethylpolysiloxanes, foam stabilizers such as the fatty acid sugaresters, preservatives, lubricants such as talc, magnesium stearate,finely divided amorphous pyrogenic silicas, etc.

Tablet binders and fillers suitable for use herein includepolyvinylpyrrolidone, poly (oxyethylene) of molecular weight 20,000 to500,000, polyethyleneglycols of molecular weight of from about 1000 toabout 50,000, Carbowax having a molecular weight of from 4000 to 20,000,nonionic surfactants, fatty acids, sodium carboxymethyl cellulose,gelatin, fatty alcohols, clays, polymeric polycarboxylates, sodiumcarbonate, calcium carbonate, calcium hydroxide, magnesium oxide,magnesium hydroxide carbonate, sodium sulfate, proteins, celluloseethers, cellulose esters, polyvinyl alcohol, alginic acid esters,vegetable fatty materials of a pseudocolloidal character. Of the above,polyethyleneglycols are highly preferred, especially those havingmolecular weight of from about 1,000 to about 30,000, preferably fromabout 12,000 to about 30,000.

Chelating agents beneficially aid cleaning and bleach stability bykeeping metal ions, such as calcium, magnesium, and heavy metal cationsin solution. Examples of suitable chelating agents include sodiumtripolyphosphate, sodium acid pyrophosphate, tetrasodium pyrophosphate,aminopolycarboxylates such as nitrilotriacetic acid and ethylenediaminetetracetic acid and salts thereof, ethylenediamine-N,N'-disuccinic acid(EDDS) and salts thereof, and polyphosphonates and aminopolyphosphonatessuch as hydroxyethanediphosphonic acid, ethylenediaminetetramethylenephosphonic acid,diethylenetriaminepentamethylenephosphonic acid and salts thereof. Thechelating agent selected is not critical except that it must becompatible with the other ingredients of the denture cleanser when inthe dry state and in aqueous solution. Advantageously, the chelatingagent comprises between 0.1 and 60 percent by weight of the compositionand preferably between 0.5 and 30 percent. Phosphonic acid chelatingagents, however, preferably comprise from about 0.1 to about 1 percent,preferably from about 0.1% to about 0.5% by weight of composition.

Enzymes suitable for use herein are exemplified by proteases, alkalases,amylases, fungal and bacterial lipases, dextranases, mutanases,glucanases, esterases, cellulases, pectinases, lactases and peroxidases,etc. Suitable enzymes are discussed in U.S. Pat. No. 3,519,570 and U.S.Pat. No. 3,533,139.

The following Examples further describe and demonstrate the preferredembodiments within the scope of the present invention.

EXAMPLES I TO V

The following are representative denture cleansing tablets according tothe invention. The percentages are by weight of the total tablet. Thetablets are made by compressing a mixture of the granulated componentsin a punch and dye tabletting press at a pressure of about 105 kPa.

    ______________________________________                                                       I    II     III    IV   V                                      ______________________________________                                        Malic Acid       12     10     15   --   14                                   Citric Acid      --     10     --   15   --                                   Sodium Carbonate 10     8      10   6    10                                   Sulphamic Acid   5      --     --   3    3                                    PEG 20,000       --     3      7    8    5                                    PVP 40,000       6      3      --   --   --                                   Sodium Bicarbonate                                                                             23     24     25   23   24                                   Sodium Perborate Monohydrate                                                                   15     12     16   30   15                                   Potassium Monopersulphate                                                                      15     18     13   --   14                                   Pyrogenic Silica --     3      1    1    --                                   Talc             2      --     --   --   --                                   EDTA             --     --     1    --   3                                    EDTMP.sup.1      1      --     --   1    --                                   Flavor.sup.5     2      1      2    1    2                                    Magnasoft Fluid.sup.4                                                                          1      1.5    0.5  2    1                                    Bleach Precursor Agglomerate                                                                   9      8      10   12   10                                   Bleach Precursor Agglomerate                                                  TAED.sup.2       2      --     4    5    2.5                                  TMHOS.sup.3      2      3      --   --   --                                   Sulphamic Acid   2      2      2    2    3.5                                  Sodium Bicarbonate                                                                             0.5    0.2    0.2  0.5  2                                    PEG 6000         2.5    2      2.4  2.5  1.5                                  Dye              --     0.8    1.4  2    0.5                                  ______________________________________                                         .sup.1 Ethylenediaminetetramethylenephosphonic acid                           .sup.2 Tetraacetylethylene diamine                                            .sup.3 Sodium 3,5,5trimethylhexanoyloxybenzene sulfonate                      .sup.4 Magnasoft Fluid  supplied by OSI                                       .sup.5 Peppermintbased flavor                                            

In Examples I to V above, the overall tablet weight is 3 g; diameter 25mm.

The denture cleansing tablets of Examples I to V display improvedantiplaque, cleansing and anti-bacterial activity together withexcellent cohesion and other physical and in-use performancecharacteristics.

EXAMPLES VI TO IX

The following are representative perfume, flavour, coolant andantimicrobial compositions according to the invention. The percentagesare by weight of total composition.

    ______________________________________                                                       VI    VII     VIII    IX                                       ______________________________________                                        PPG-5-ceteth-20  3.0     3.0     4.5   3.0                                    PEG-40 hydrogenated castor                                                                     --      1.8     4.5   3.0                                    oil                                                                           Trideceth-12     2.0     --      --    --                                     Trideceth-9      --      2.0     --    3.0                                    Flavor.sup.5     2.0             3.0                                          Perfume.sup.6    --      3.0     --    --                                     Trimethyl butanamide                                                                           0.3     0.5     --    --                                     Triclosan        --      --      1.0   0.5                                    Magnasoft Fluid.sup.4                                                                          1.0     1.5     5.0   1.0                                    Water            <---- ---- to 100% ---- ---- >                               ______________________________________                                    

The perfume, flavor, coolant and/or antimicrobial compositions ofExamples VI to IX display improved surface-substantivity, impact and/orefficacy.

I claim:
 1. A method of improving the stability of a bleach andlipophile composition comprising an inorganic persalt bleaching agentand a lipophile selected from the group consisting of flavorants,perfumes, physiological coolants, antimicrobial agents and mixturesthereof, by inclusion of a aminoalkyl silicone having an aminoalkylsiloxane content of from 0.1% to 2% on a repeating unit basis.
 2. Themethod of claim 1 wherein the composition is a denture cleanser.
 3. Themethod of claim 1 wherein the inorganic persalt bleaching agentcomprises one or more bleaching agents selected from the groupconsisting of alkali metal persulfates, alkali metal perborates andmixtures thereof.
 4. The method of claim 1 wherein the flavorantcomprises one or more flavor components selected from the groupconsisting of wintergreen oil, oregano oil, bay leaf oil, peppermintoil, spearmint oil, clove oil, sage oil, sassafras oil, lemon oil,orange oil, anise oil, benzaldehyde, bitter almond oil, camphor, cedarleaf oil, marjoram oil, citronella oil, lavendar oil, mustard oil, pineoil, pine needle oil, rosemary oil, thyme oil, cinnamon leaf oil, andmixtures thereof.
 5. The method of claim 1 wherein the perfume comprisesone or more perfume components selected from the group consistinggeranyl acetate, linalyl acetate, citronellyl acetate, dihydromyrcenylacetate, terpinyl acetate, tricyclodecenyl acetate, tricyclodecenylpropionate, 2-phenylethyl acetate, benzyl acetate, benzyl salicylate,benzyl benzoate, styrallyl acetate, amyl salicylate, methyldihydrojasmonate, phenoxyethyl isobutyrate, neryl acetate,trichloromethyl-phenylcarbinyl acetate, p-tertiary butyl-cyclohexylacetate, isononyl acetate, cedryl acetate, vetiveryl acetate, benzylalcohol, 2-phenylethanol, linalool, tetrahydrolinalool, citronellol,dimethylbenzylcarbinol, dihydromyrcenol, tetrahydromyrcenol, terpineol,eugenol, geraniol, vetiverol, 3-isocamphyl-cyclohexanol,2-methyl-3-(p-tertiary butylphenyl)-propanol,2-methyl-3-(p-isopropylphenyl)-propanol, 3-(p-tertiarybutylphenyl)-propanol, nerol, alpha-n-amylcinnamic aldehyde,alpha-hexyl-cinnamic aldehyde,4-(4-hydroxy-4-methylpentyl)-3-cyclohexenecarbaldehyde,4-(4-methyl-3-pentenyl)-3-cyclohexenecarbaldehyde,4-acetoxy-3-pentyl-tetrahydropyran, 2-n-heptyl-cyclopentanone,3-methyl-2-pentyl-cyclopentanone, n-decanal, n-dodecanal,hydroxycitronellal, phenylacetaldehyde dimethyl acetal,phenylacetaldehyde diethyl acetal, geranonitrile, citronellonitrile,cedryl methyl ether, isolongifolanone, aubepine nitrile, aubepine,heliotropine, coumarin, vanillin, diphenyl oxide, ionones, methylionones, isomethyl ionones, irones, cis-3-hexenol and esters thereof,indane musks, tetralin musks, isochroman musks, macrocyclic ketones,macrolactone musks, ethylene brassylate, aromatic nitromusks/8ndmixtures thereof.
 6. The method of claim 1 additionally comprising aneffervescence generator.
 7. The method of claim 1 wherein theaminoalkylsilicone is a noncyclic, hydrophobic aminoalkylsilicone havinga formula comprising two basic units:1) (R¹)_(m) (R)_(n)SiO.sub.(4-m-n)/2 wherein m+n is 1, 2 or 3; n is 1, 2 or 3; m is 0, 1,2; and 2) (R¹)_(a) (R²)_(b) SiO.sub.(4-a-b)/2 wherein a+b is 1, 2, or 3,and a and b are integers,wherein R¹ and R² are independently selectedfrom the group consisting of H, alkyl and alkenyl of about 1 to about 10carbons optionally substituted with fluoro or cyano groups, hydroxy,alkoxy, and acetoxy, and R is ##STR4## wherein R³ is a divalent alkyleneof about 1-20 carbon atoms optionally substituted or interrupted by Oatoms, R⁴, R⁵ and R⁶ which may be the same or different are selectedfrom the group consisting H, alkyl of about 1-20 carbons optionallysubstituted or interrupted by N, O atoms and mixtures thereof, and X⁻ isa monovalent anion.
 8. The method of claim 7 wherein the aminoalkylsilicone has a molecular weight of at least about 5,000.
 9. The methodof claim 8 wherein the aminoalkyl silicone has a molecular weight offrom about 5000 to about 100,000.
 10. The method of claim 1 comprisingfrom about 0.01% to about 25%, by weight of the aminoalkyl silicone. 11.The method of claim 10 comprising from about 0.1% to about 5% by weightof the aminoalkyl silicone.
 12. The method of claim 1 additionallycomprising an organic peroxyacid bleach precursor.
 13. The method ofclaim 12 wherein the organic peroxyacid bleach precursor is selectedfrom the group consisting of acylated polyalkyldiamines, especiallytetraacetylethylenediamine, and carboxylic esters having the generalformula AcL wherein Ac is the acyl moiety or an organic carboxylic acidcomprising an optionally substituted, linear or branched C₆ -C₂₀ alkylor alkenyl moiety or a C₆ -C₂₀ alkyl-substituted aryl moiety and L is aleaving group, the conjugate acid of which has a pKa in the range from 4to 13.